What you are describing is called
Lamarckian Evolution, a thoroughly discredited theory of evolution (as opposed to evolution by natural selection). By the logic of Lamarckian Evolution, a weightlifter's sons would all grow up to have powerful muscles because their father did, and generations of successive weightlifters would become more and more muscular.
While it may be true that a family of weightlifters get better and better at weightlifting, this is not due to an inherited skill at weightlifting but likely because weightlifter fathers pass on the secrets (verbally and through training) of how to better lift weights as well as teaching their sons the discipline to keep lifting weights all day. Sons abducted at birth from weightlifter fathers generally do not grow up with powerful muscles because their natural fathers were weightlifters, unless they themselves became weightlifters independently.
There is also a chicken-egg causality to consider. Some genetics lines code for stronger muscles (by random happenstance), which is inherited by children. If families are known to produce stronger children, it is more likely that a person with a natural disposition to develop strong muscles will become a weightlifter because it is easier and more productive than someone without that genetic advantage. This continued advantage might lead to a line of weightlifters who are weightlifters because they are genetically advantaged toward strength rather than being strong because they are genetically weightlifters.
Consider Father Onan, who has sons Adam, Bart and Cain. Father Onan is a strong man with good spatial awareness and found his aptitude made carpenting easy. Adam grows up with Onan's strength and awareness. Bart grows up with more strength and the same awareness. Cain grows up with less awareness but the same strength. Father Onan trains all three as carpenters. Adam proves a capable carpenter. Bart proves an excellent carpenter. Cain is not such a good carpenter and becomes a draughtsman instead. Bart has three children, two of whom lack the awareness to be good carpenters, one of whom has inherited his father's aptitude. That son becomes a carpenter, the others become draughtsmen as well. Bart's grandchildren inherit their father's ability, one of whom is both far stronger and more aware than their great-grandfather
through pure chance. That last son becomes the greatest carpenter in the realm because he is naturally suited to becoming a carpenter.
We look at the last son and think 'he is descended from a long line of carpenters, of course he is good', but even assuming no additional skills were developed between the four generations, dozens of sons and grandchildren did not become carpenters because they were less disposed - the circumstances selected against them being carpenters. Since only the best became carpenters to live up to their fathers' legacies, it gives the illusion of carpentry being an inherited trait.
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Topic: The Dynasties of Cairnwood Crossing -Beginning of Turn 4 (Read 14851 times)